Many types of communications can be performed over data networks (wireless and/or wireline networks), including electronic mail, web browsing, file downloads, electronic commerce transactions, voice or other forms of real-time, interactive communications, and others. To enable the establishment of communications sessions in a network, various control functions are deployed in the network. Some standards bodies have defined subsystems within communications networks that include such control functions. One such standards body is the Third Generation Partnership Project (3GPP), which has defined an Internet protocol (IP) multimedia subsystem (IMS) that includes various control functions for provision of IP multimedia services, including audio, video, text, chat, or any combination of the foregoing.
An IP multimedia subsystem can be used in conjunction with a wireless network, such as wireless networks according to the GSM (Global System for Mobile) or UMTS (Universal Mobile Telecommunications System) standards, as defined by 3GPP, or wireless networks according to CDMA 2000 (Code Division Multiple Access 2000), as defined by 3GPP2. An IP multimedia subsystem can also be used with wireline networks. In the 3GPP2 context, the equivalent of the IP multimedia subsystem is sometimes referred to as a multimedia domain (MMD) network. In the wireline context, the equivalent of an IP multimedia subsystem is sometimes referred to as a Next Generation Networks (NGN). The term “multimedia network” is used to generically refer to any one of an IP multimedia subsystem, MMD network, NGN, or to any other network in which multimedia communications (any one or more of video, audio, text, chat, e-mail, web browsing, etc.) are possible.
An issue associated with conventional multimedia networks is the adequacy of security. Generally, standards bodies have not adequately defined procedures and mechanisms to provide comprehensive security within multimedia networks.